How to retrieve image from public folder and convert to base64 in Laravel?

I want to get the image file from my public folder which I stored all of my images, then convert to base64. I will use the base64 image to view it on PDF using pdfmake in dataTables, because my dataTable cell have an Image called avatar, and as I've searched it needs to convert image to base64 to able to view in PDF.

Now I use file_get_contents to retrieve my image, but my page is too much load I guess it's around 5mins, and after throws and error Maximum execution time of 60 seconds exceeded.

via Chebli Mohamed